USB to I2S: M2Tech vs XMOS vs Open-source Qnktc

[juanito]

I sell the M2Tech USB to I2S module by AckoDAC (https://sites.google.com/site/ackodac/home) at 80 euro + shipping

Hi, may be I'm on the wrong thread, but now I see you tested QNKTC DAC: have you had any issues with this DAC and Mac OSX?

I have this DAC. With windows and Asio plus Foobar 2000 it works perfect. But I recently bought an Imac with OSX (snow leopard) and when using this DAC with itune or VLC media player or Cog player (there is no foobar for mac), after a while I have distortion in sound. It's very strange because it works fine for a few songs and then it's a kind of electric distortion. I'm going to install a windows partition and try also. But it surprise me because I saw that OSX doesn't need any Asio drivers, it's natively. I also changed settings with Midi Application, but nothing at all goes on.
Well if you heard any thing similar with these Dac's and OSX I would appreciate much your help.
Thanks. Bye.
JOHN

 

[audiodesign]

Try the player used by me

 

[MrSlim]

Hi, may be I'm on the wrong thread, but now I see you tested QNKTC DAC: have you had any issues with this DAC and Mac OSX?

I have this DAC. With windows and Asio plus Foobar 2000 it works perfect. But I recently bought an Imac with OSX (snow leopard) and when using this DAC with itune or VLC media player or Cog player (there is no foobar for mac), after a while I have distortion in sound. It's very strange because it works fine for a few songs and then it's a kind of electric distortion. I'm going to install a windows partition and try also. But it surprise me because I saw that OSX doesn't need any Asio drivers, it's natively. I also changed settings with Midi Application, but nothing at all goes on.
Well if you heard any thing similar with these Dac's and OSX I would appreciate much your help.
Thanks. Bye.
JOHN

You'd probably be better served by posting your question on this thread:
http://www.diyaudio.com/forums/digital-source/185761-open-source-usb-interface-audio-widget.html

 

[2A3SET]

Passive I/V for 1955

Andrea,

Can we run AD1955 passive like this to be compliant with the datasheet? With 2K load, there should be about 400mv RMS at output.

Thanks

 

[audiodesign]

I have tested many configurations with AD1955 and output transformers but always I get bad results (http://www.ti.com/lit/an/slaa399/slaa399.pdf).

To get a flat frequency response and low distortion the best method is a pure resistor followed by a high impedance stage like a vacuum tube.

The 200 ohm value has been found after many test from 47 to 2Kohm.

I should receive soon the first pcb of my hybrid output stage.
USB DAC 2 - Hi-Resolution System

Qh (http://www.quanghao.com/)will sell these pcb and the complete kit at very low cost.

 

[2A3SET]

Thanks Andrea, looking forward to your SEN I/V test.

I have tested many configurations with AD1955 and output transformers but always I get bad results (http://www.ti.com/lit/an/slaa399/slaa399.pdf).

To get a flat frequency response and low distortion the best method is a pure resistor followed by a high impedance stage like a vacuum tube.

The 200 ohm value has been found after many test from 47 to 2Kohm.

I should receive soon the first pcb of my hybrid output stage.
USB DAC 2 - Hi-Resolution System

Qh (http://www.quanghao.com/)will sell these pcb and the complete kit at very low cost.

 

[audiodesign]

Here the controller to get data from XMOS module and configure any DAC like AD1955, DSD1794, ES9018 ....

IR remote command for the volume and mute.

M2Tech and Open-source Qnktc sold.

 

[Telstar]

Here the controller to get data from XMOS module and configure any DAC like AD1955, DSD1794, ES9018 ....

IR remote command for the volume and mute.

The volume attenuation uses the extra 8 bits of the xmos chip?

 

[audiodesign]

Which bits ?

The volume use the special DAC function of the new DAC chips so no lost in resolution and no changes on on the analog signal

 

[Telstar]

Which bits ?

The volume use the special DAC function of the new DAC chips so no lost in resolution and no changes on on the analog signal

Nevermind then.
I didnt know also dsd1794 had a volume function.

 

[audiodesign]

DSD1794 Digital Attenuation: 0 dB to –120 dB,0.5 dB/Step
AD1955 On-Chip Clickless Volume Control
ES9018 On-Chip Clickless Volume Control
PCM1794 NO
PCM1796 Digital Attenuation: 0 dB to –120 dB,0.5 dB/Step
PCM1792 Digital Attenuation: 0 dB to –120 dB,0.5 dB/Step

 

[palmito]

Do know when, if, the "Hybrid Output Stage 2" pcb from the "USB DAC 2 - Hi-Resolution System" will be available for sale? Thanks.

 

[audiodesign]

Very soon, I am waiting in the next weeks the first pcb to test it

 

[UnixMan]

The volume use the special DAC function of the new DAC chips so no lost in resolution and no changes on on the analog signal

are you sure? how does those functions works?

 

[fralippo]

Another USB to I2S board that might be interesting to compare is the exD audio, that also has the interesting feature to output LJ24 signals, very useful for a direct connection to the PCM1704 DACs. Do someone have informations on it?

 

[gana]

Hello

I forgot to mention the USB -> I2S device I am currently using so the units I am using that are worth mentioning are: Light Harmonic Titan USB -> I2S, M2Tech USB -> I2S, QNKTC / Audio Widget USB -> I2S and exaU2I USB -> I2S...

Hello i started to test and translate i2s to TDM but i have no experience but still trying harder.. i red many of papers that how i2s works but no clear small examples for programming on c or c++. first i want to have little example that how to pragramming i2s and want to test my own source of kit based on XMOS with appropriate software.

My kit is USB AUDIO Multi Channel kit. i lost much time i want it step by step but its is too late to do that because i have few weeks to finish my project.

May it stupid questions for you but i couldnt find such a example and software yet. Any one advice or lead me would be appreciated.. thanks